<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://cdn.jsdelivr.net/npm/vue@2.6.10/dist/vue.js"></script>
</head>
<style>
    .one {
        width: 100px;
        height: 100px;
        background-color: antiquewhite;
    }

    .two {
        width: 300px;
        height: 300px;
        background-color: aqua;
    }

    .three {
        width: 400px;
        height: 400px;
        background-color: aquamarine;
    }

    .active {
        color: pink;
    }
</style>

<body>
    <div id="app">
        <div :class="['one','two','three']"></div>
        <div class="active" :class="boxClass"></div>
    </div>

    <script>
        Vue.config.productionTip = false;

        const vm = new Vue({
            el: "#app",
            data() {
                return {
                    //class强制绑定写法1:值是一个字符串
                    // className:"one"/
                    //class强制绑定写法2:值是一个对象写法,对象的key就是类型,如果这个key对应的value是truthy的值,则这个类开启//
                    // className:{
                    //     one:false,
                    //     two:true,
                    // }
                    //class强制绑定写法3：值是一个数组
                    //数组中的每一个值都会作为当前元素的类名

                    boxClass: ["one", "two", "three"],
                }
            }
        })
    </script>
</body>

</html>